1. Field of the Invention
This invention relates generally to control systems and data structures for multifunction computer peripheral devices such as scanners and printers and, more particularly, to redefining resolution qualities for various scanning and printing functions.
2. Related Art
Computer peripheral devices that combine functions such as scanning, printing and faxing are becoming increasingly popular in the marketplace. Building a single device that can perform scan, print, copy, and/or fax functions according to pre-existing standards for those operations presents a variety of control system programming challenges. One of these challenges is resolution quality control.
Control systems for varying resolution quality in single function devices are known. For example, a control system for an inkjet printer that selectively prints different resolutions is disclosed in U.S. Pat. No. 4,097,873 to Martin. A control system for varying scanner resolutions is disclosed in U.S. Pat. No. 6,160,249 to Webb, et al. A control system for converting facsimile image transmissions is disclosed in U.S. Pat. No. 6,130,966 to Sekine, et al. These control systems do not disclose varying resolution quality for multi-function devices.
Multi-function computer peripherals that already exist in the market place typically offer a user the desirable option of selecting a resolution quality by inputting a designated resolution quality which the user selects from among a variety of resolution quality options. Typically each selectable resolution is associated with a scan resolution and a print resolution. Both scan resolutions and print resolutions are defined by a predetermined number of dots per inch (dpi) in both the horizontal and vertical directions.
Integrated multi-function computer peripherals by definition offer two or more of a plurality of functions which may include black and white copying, color copying, photograph quality copying, faxing, scanning to files and scanning to e-mail. An operation panel allows a user to input a function designation from among two or more of these choices.
As with all computing devices, there is a continuing need for increasing efficiency by increasing speed, decreasing memory space required and decreasing the possibility of unacceptable output. For each imaging function, there are more efficient resolutions and less efficient resolutions. For at least some functions there are resolution limits beyond which unacceptable results will be output. For most functions, there is a range of resolutions that will output acceptable results. However, within these acceptable ranges, there remains a variance between more efficient resolutions and less efficient resolutions. For some functions, there are optimal resolutions.
Inefficiencies arise with multi-function devices when a user inputs a designated resolution which is not an efficient resolution for a user input designated function. For example, fax modems do not support a resolution higher than 150 dpi. If a user has input a designated resolution higher than 150 dpi and also input a designated function as faxing, execution of the operation will be unnecessarily slowed and memory demand will be unnecessarily increased by scanning the image at any range above 150 dpi.
Similarly, if the user inputs a high designated resolution of 600 by 1200 dpi for scanning and 2400 by 1200 dpi for printing, and thereafter inputs black and white copying as the designated function, there will be an inefficient slowing of scanner time and increase in memory space used over and above the maximum resolution supportable for black and white copying. Hence, there is a need in the multi-function computer peripheral control system arts for a control system that will redefine quality resolution to a lower resolution for functions such as faxing and black and white copying when a user has inappropriately or inadvertently designated an unsupportably high resolution quality.
Increasing efficiency is not limited to decreasing resolutions. For example, if a user has input as a designated function photograph quality copying, but has neglected to input the highest resolution quality as the designated resolution, a photograph may be both scanned and printed at a resolution too low to yield an acceptable copy. The scan and copy function would then need to be executed a second time, which is inefficient for the user. Accordingly, there is a need for a control system that will increase the resolution that is executed for a high resolution designated function, when a low quality has been input as the designated resolution.
Generally, there is a need in the multi-function computer peripheral arts for a control system that compares a user input designated resolution for a user input designated function to a range of resolutions efficient for that function and redefines the resolution to be executed with that function where appropriate. Where a user has input a designated resolution that is outside the limit of efficient resolutions for a designated function, there is a need for a control system that will redefine the resolution to be executed within acceptable limits. Where a user has input a designated resolution that is within a range of acceptable resolutions for a designated function, but nevertheless is not an optimal resolution, there is a need for a control system that will redefine the resolution at which the function is to be executed at a more efficient resolution than that designated by the user.